That is one very long and complicated class. It could do with some refactoring to simplify. All those If statements and the nested if statements are all code smells.
>The AVI support seems to work. As for the TXT file type, this cannot be done at the signature level. So, we can only rely on the extension.
>
>Here is the class:
>
>
>Namespace Framework
>
> Public Class FileType
>
> Public cExtension As String = ""
> Public cFile As String = ""
> Public cMessage As String = ""
> Public nNoFileType As Integer = 0
> Private oApp As Framework.App = Nothing
> Private oProcess As Framework.LXProcess = Nothing
>
> ' This is when we access the class in a desktop mode
> Sub New(ByVal toApplication As Framework.App)
> oApp = toApplication
> End Sub
>
> ' This is when we access the class in a Web or Web Service mode
> Public Sub New(ByVal toProcess As Framework.LXProcess)
> oProcess = toProcess
> oApp = oProcess.oApp
> End Sub
>
> ' Return the file type
> ' expC1 File name with the full path
> Public Function FileType() As Boolean
> Dim lcDirectory As String = ""
> Dim lcExtension As String = ""
> Dim lcFile As String = ""
> Dim lcString As String = ""
> Dim lcValue As String = ""
> Dim lnLocation As Integer = 0
> Dim loDirectoryFunction As Framework.DirectoryFunction = Nothing
> Dim loFileDirectory As Framework.FileDirectory = Nothing
> Dim loFileFunction As Framework.FileFunction = Nothing
> Dim loXml As Framework.XML = Nothing
> Dim loZip As Framework.Zip = Nothing
>
> ' Get the proper definition as per the current scope
> If oProcess Is Nothing Then
> loDirectoryFunction = New Framework.DirectoryFunction(oApp)
> loFileDirectory = New Framework.FileDirectory(oApp)
> loFileFunction = New Framework.FileFunction(oApp)
> loXml = New Framework.XML(oApp)
> loZip = New Framework.Zip(oApp)
> Else
> loDirectoryFunction = New Framework.DirectoryFunction(oProcess)
> loFileDirectory = New Framework.FileDirectory(oProcess)
> loFileFunction = New Framework.FileFunction(oProcess)
> loXml = New Framework.XML(oProcess)
> loZip = New Framework.Zip(oProcess)
> End If
>
> ' Reset everything
> cExtension = ""
> cMessage = ""
> nNoFileType = 0
>
> ' Initialization
> lcFile = Trim(cFile)
>
> ' Read it as a binary
> lcString = oApp.FileToStrBinary(lcFile)
>
> ' If we have less than four characters
> If lcString.Length < 4 Then
> Return False
> End If
>
> ' If this is a JPG
> If Left(lcString, 3) = Chr(255) + Chr(216) + Chr(255) Then
> cExtension = "JPG"
> nNoFileType = 6
> Return True
> End If
>
> ' If this is a GIF
> If Left(lcString, 3) = "GIF" Then
> cExtension = "GIF"
> nNoFileType = 7
> Return True
> End If
>
> ' If this is a EMF
> If Mid(lcString, 42, 3) = "EMF" Then
> cExtension = "EMF"
> nNoFileType = 13
> Return True
> End If
>
> ' If this is a WMF
> If Left(lcString, 4) = Chr(215) + Chr(205) + Chr(198) + Chr(154) Then
> cExtension = "WMF"
> nNoFileType = 14
> Return True
> End If
>
> ' If this is a TIF
> If Left(lcString, 4) = Chr(77) + Chr(77) + Chr(0) + Chr(42) Then
> cExtension = "TIF"
> nNoFileType = 15
> Return True
> End If
>
> ' If this is a PNG
> If Left(lcString, 4) = Chr(137) + "PNG" Then
> cExtension = "PNG"
> nNoFileType = 12
> Return True
> End If
>
> ' If this is a BMP
> If Left(lcString, 2) = "BM" Then
> cExtension = "BMP"
> nNoFileType = 16
> Return True
> End If
>
> ' If this is a SWF
> If Left(lcString, 3) = "CWS" And Asc(Mid(lcString, 4, 1)) < 16 Then
> cExtension = "SWF"
> nNoFileType = 8
> Return True
> End If
>
> ' If this is a SWF
> If Left(lcString, 3) = "FWS" And Asc(Mid(lcString, 4, 1)) < 16 Then
> cExtension = "SWF"
> nNoFileType = 8
> Return True
> End If
>
> ' If this is a XML
> If UCase(Left(lcString, 6)) = "<?XML " Then
> cExtension = "XML"
> nNoFileType = 10
> Return True
> End If
>
> ' If this is a DOC
> If Left(lcString, 8) = Chr(208) + Chr(207) + Chr(17) + Chr(224) + Chr(161) + Chr(177) + Chr(26) + Chr(225) Then
> cExtension = "DOC"
> nNoFileType = 1
> Return True
> End If
>
> ' If this is a PDF
> If UCase(Left(lcString, 5)) = "%PDF-" Then
> cExtension = "PDF"
> nNoFileType = 2
> Return True
> End If
>
> ' If this is a Excel
> If Left(lcString, 8) = Chr(208) + Chr(207) + Chr(17) + Chr(224) + Chr(161) + Chr(177) + Chr(26) + Chr(225) Then
> cExtension = "XLS"
> nNoFileType = 3
> Return True
> End If
>
> ' If this is a Microsoft Office 2007 document
> If Left(lcString, 14) = Chr(80) + Chr(75) + Chr(3) + Chr(4) + Chr(20) + Chr(0) + Chr(6) + Chr(0) + _
> Chr(8) + Chr(0) + Chr(0) + Chr(0) + Chr(33) + Chr(0) Then
>
> ' If we have a temporary directory
> If oApp.cTempDir.Length > 0 Then
>
> ' Get a temporary file name
> lcDirectory = oApp.GenerateFileName()
>
> ' Get the full long directory name
> lcDirectory = oApp.cTempDir + lcDirectory
>
> ' If we can create a temporary directory under Temp
> If oApp.CreateDirectory(lcDirectory) Then
>
> ' Zip class needs an extension, otherwise, it will try to zip a file name ending with .zip
> loFileFunction.cSource = lcFile
> loFileFunction.cDestination = lcFile + ".zip"
> loFileFunction.lLogError = False
> If loFileFunction.CopyFile() Then
>
> ' If we can unzip the file
> loZip.cFile = lcFile + ".zip"
> loZip.cDirectory = lcDirectory
> loZip.lUseCommandPrompt = True
> If loZip.Unzip() Then
>
> ' Delete the temporary file
> If Not loFileFunction.DeleteFile(lcFile + ".zip", False) Then
> End If
>
> ' If we can load the Xml
> If loXml.LoadXmlFromFile(lcDirectory + "\[Content_Types].xml") Then
>
> ' Delete the temporary files which were created in the temporary directory
> loFileDirectory.cDirectory = lcDirectory
> loFileDirectory.GetFile()
> If Not loFileDirectory.DeleteFiles() Then
> End If
>
> ' Delete the temporary directory
> If Not loDirectoryFunction.DeleteDirectory(lcDirectory) Then
> End If
>
> ' If we can add the namespace
> If loXml.AddNamespace("http://schemas.openxmlformats.org/package/2006/content-types", "ns") Then
>
> ' If the attribute exists
> If loXml.IsXMLNodeAttribute("//ns:Types/ns:Override[1]", "PartName") Then
>
> ' Get the value of the attribute
> If loXml.GetXMLNodeAttributeValue("//ns:Types/ns:Override[1]", "PartName") Then
> lcValue = loXml.cNodeAttribute
>
> ' Based on the type
> Select Case lcValue
>
> ' Word
> Case "/word/document.xml"
> cExtension = "DOCX"
> nNoFileType = 17
> Return True
>
> ' Excel
> Case "/xl/workbook.xml"
> cExtension = "XLSX"
> nNoFileType = 18
> Return True
>
> ' PowerPoint
> Case "/ppt/presentation.xml"
> cExtension = "PPTX"
> nNoFileType = 19
> Return True
>
> Case Else
> Return False
>
> End Select
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Else
> Return False
> End If
>
> Return False
> End If
>
> ' If this is a ZIP
> If Left(lcString, 4) = "PK" + Chr(3) + Chr(4) Then
> cExtension = "ZIP"
> nNoFileType = 9
> Return True
> End If
>
> ' If this is a Windows AVI Video
> If Left(lcString, 4) = Chr(82) + Chr(73) + Chr(70) + Chr(70) And _
> Mid(lcString, 9, 8) = Chr(65) + Chr(86) + Chr(73) + Chr(32) + Chr(76) + Chr(73) + Chr(83) + Chr(84) Then
> cExtension = "AVI"
> nNoFileType = 4
> Return True
> End If
>
> ' If this is a Powerpoint file
> If Mid(lcString, 513, 4) = Chr(160) + Chr(70) + Chr(29) + Chr(240) Then
> cExtension = "PPT"
> nNoFileType = 5
> Return True
> End If
>
> ' If we have not found any type with the binary approach, we will try to rely on the extension
> lnLocation = oApp.RAt(".", lcFile)
>
> ' If we have found the extension
> If lnLocation > 0 Then
>
> ' Get the extension
> lcExtension = Mid(lcFile, lnLocation + 1)
>
> ' Make it uppercase
> lcExtension = UCase(lcExtension)
>
> ' If this is a TXT file
> If lcExtension = "TXT" Then
> cExtension = "TXT"
> nNoFileType = 11
> Return True
> End If
>
> End If
>
> Return True
> End Function
>
> End Class
>
>End Namespace
>
Craig Berntson
MCSD, Microsoft .Net MVP, Grape City Community Influencer
